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diff --git a/doc/man7/EVP_MAC-GMAC.pod b/doc/man7/EVP_MAC-GMAC.pod
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+=pod
+
+=head1 NAME
+
+EVP_MAC-GMAC - The GMAC EVP_MAC implementation
+
+=head1 DESCRIPTION
+
+Support for computing GMAC MACs through the B<EVP_MAC> API.
+
+This implementation uses EVP_CIPHER functions to get access to the underlying
+cipher.
+
+=head2 Identity
+
+This implementation is identified with this name and properties, to be
+used with EVP_MAC_fetch():
+
+=over 4
+
+=item "GMAC", "provider=default" or "provider=fips"
+
+=back
+
+=head2 Supported parameters
+
+The general description of these parameters can be found in
+L<EVP_MAC(3)/PARAMETERS>.
+
+The following parameter can be set with EVP_MAC_CTX_set_params():
+
+=over 4
+
+=item "key" (B<OSSL_MAC_PARAM_KEY>) <octet string>
+
+Sets the MAC key.
+Setting this parameter is identical to passing a I<key> to L<EVP_MAC_init(3)>.
+
+=item "iv" (B<OSSL_MAC_PARAM_IV>) <octet string>
+
+Sets the IV of the underlying cipher, when applicable.
+
+=item "cipher" (B<OSSL_MAC_PARAM_CIPHER>) <UTF8 string>
+
+Sets the name of the underlying cipher to be used.
+
+=item "properties" (B<OSSL_MAC_PARAM_PROPERTIES>) <UTF8 string>
+
+Sets the properties to be queried when trying to fetch the underlying cipher.
+This must be given together with the cipher naming parameter to be considered
+valid.
+
+=back
+
+The following parameters can be retrieved with
+EVP_MAC_CTX_get_params():
+
+=over 4
+
+=item "size" (B<OSSL_MAC_PARAM_SIZE>) <unsigned integer>
+
+Gets the MAC size.
+
+=back
+
+The "size" parameter can also be retrieved with EVP_MAC_CTX_get_mac_size().
+The length of the "size" parameter is equal to that of an B<unsigned int>.
+
+=head1 SEE ALSO
+
+L<EVP_MAC_CTX_get_params(3)>, L<EVP_MAC_CTX_set_params(3)>,
+L<EVP_MAC(3)/PARAMETERS>, L<OSSL_PARAM(3)>
+
+=head1 COPYRIGHT
+
+Copyright 2018-2021 The OpenSSL Project Authors. All Rights Reserved.
+
+Licensed under the Apache License 2.0 (the "License").  You may not use
+this file except in compliance with the License.  You can obtain a copy
+in the file LICENSE in the source distribution or at
+L<https://www.openssl.org/source/license.html>.
+
+=cut